Apparatus for discharging and heating aggregate for the making of concrete

ABSTRACT

Aggregate flows downwardly in a vertical silo over mutually crossing, substantially horizontal chutes. A heater and air blower located near the vault discharge port blows air upwardly, which is discharged in the vicinity of the chute crossing points.

United States Patent Vaananen Nov. 18, 1975 APPARATUS FOR DISCHARGING AND [56] References Cited HEATING AGGREGATE FOR THE MAKING UNITED STATES PATENTS OF CONCRETE 2,900,109 8/1959 Hoopes et a1 222/146 HS [76] Inventor: Onni Olavi Vaananen, Porttikuja 2 2,907,501 10/1959 Laird 222/564 x F 68, 00940 Helsinki 94, Finland 3,182,859 5/1965 Harris et al. 222/146 HS F' [22] [led Mar 1974 Primary ExaminerA11en N. Knowles [21] Appl. No.: 452,547 Attorney, Agent, or FirmPau1 & Paul [30] Foreign Application Priority Data [57] ABSTRACT Mar. 20, 1973 Finland 858/73 Aggregate flows downwardly in a vertical $110 over mutually crossing, substantially horizontal chutes. A U-S- H; heater and air blower located near the Vault discharge Clport blows air upwardly is discharged in the vi- [58] Field Of Search 222/ 146 R, 146 HS, 146 H, cinity of the chute crossing points 8 Claims, 4 Drawing Figures US. Patent Nov. 18, 1975 Sheet 1 of 3 3,920,159

Fig. I

US. Patent Nov. 18, 1975 Sheet 2 of 3 AGGREGATE COMPONENT AGGREGATE COMPONENT U.S. Patent Nov. 18, 1975 Sheet30f3 3,920,159

' BACKGROUND AND. SUMMARYFQFTHE" lNvENTioN I w The present invention c'o ncernsanapparatus.for idischarging and heating the aggregate component for concrete making, the apparatus comprising a vertical silo through which the aggregate'is allowed to flow .downward from above, an airblow'er' andheater for. blowing heating air into the silo, and within the silo substantially horizontal, mutually crossing valut-forming members preferably shaped like downward open chutes, the blowing of'air into the silo taking place through the vaulted spaces which are formed below these.

Therein, at the crossing points of the vault-forming members there is formed a vertical flow passage, having a minimum flow resistance, for. the downwardly' flowingaggregate and for-the upwardly flowing air. By this arrangement good results have in fact already been achieved in practice.

An object of the present invention is further to develop the said apparatus so that while the amount of material required for construction of the apparatus decreases, at the same time its discharge capacity and heating capacity improve.

This aim is achieved by means of the invention owing to the characteristic that the ends of the vault-formingv chutes terminate in the vicinity of their crossing points.

In this manner it is achieved that one additional air discharge point is formed at the end of the vault-forming chute. In other words, the flow passage can be enlarged while at the same time certain parts of the vaultforming chute, which impede the downward flow of the aggregate, are totally omitted. The discharging of the aggregate becomes more uniform and the risk of permanent vault formation is reduced.

In the following the invention and its other advantages and special features are more closely described with reference to the attached drawings, wherein DESCRIPTION OF THE DRAWINGS FIG. 1 presents a schematic vertical section of an apparatus according to the invention,

DETAILED DESCRIPTION The walls of the vertical silo are indicated by the reference numeral 1. Within the silo, at a distance from the walls 1, four vertical beams 2 have been provided, two and two opposite each other. In the top lower part of conical shape of the silo a vault-forming member 3 has been provided, having the shape of a downwardly open chute. On top of the vault-forming member 3 the next vault-forming members 4 have been crosswise placed, the latter being attached by one end to the vertical beams and their other end terminating in the vicinity of the crossing point defined by the chutes. The ends of the chutes terminating close to the crossing point of the chutes 4 rest immediately on each other and thus support each other. Both ends of the vault-forming chutes 4 are open.

The blower and heater have been mounted, as a combined structural unit, on the wall of the funnel-shaped lower part of the silo to occupy a minimum of space.

J 2 The aggregate discharge opening 6 is on the same vertical as the crossing point of the vault-forming chutes 4.

The operation of the apparatus according to the invention is as follows.

The silo having been filled .with aggregate material to be discharged and heated, the blower/heater unit is started, which then through the duct 8 supplies warm air, into-the lowermost vault-forming chute 3. The

crossing points of the chutes a flow passage having a minimum air flo'w'resistance is formed, through which the greater part of the air tends to flow upward, while at the same time the aggregate flows down along the same passage. It is a feature of the present invention that in addition to the air discharging points B and C seen-in FIGS. land 2 the end of the chute 4 terminating inthe vicinity of the crossing point forms another, third air discharging point A in the same plane. The air discharge points A, B and C are fairly well equivalent as regards their flow resistance. By this means it has been possible to increase the width of the flow passage, while at the same time the amount of chute structures has in fact been reduced, which is significant not only in view of economy in structural materials but also with regard to better and more uniform flow of the aggregate, because it is obvious that any additional matter in the silo increases the risk of permanent vault formation in the aggregate.

The upward discharge of air at points A, B and C correspondingly causes a downward flow of aggregate in the vicinity of these points, whereby a kind of countercurrent effect is produced. The heated aggregate is discharged through the opening 6.

When the dry aggregate is discharged through the opening 6, it spreads stone dust into the surrounding space, causing a considerable health risk for those who are working in the space under the discharge opening 6. In order to eliminate this detriment, it has been understood'in-the present invention to place the blower/- heater unit so that its intake 5 is in the same space as the discharge opening 6 and close to it. The blower/- heater unit has then been mounted either on the bottom of the silo or attached to one side of the receiving funnel, as can be seen in FIG. 1, in which case the blower has its intake 5 at the lower end of the receiving funnel and the blowingduct 8 at the upper end of the funnel. It is hereby possible efficiently to absorb the stone powder from the working space and to blow it back into the silo.

I claim:

1. Apparatus for discharging aggregate and heating it for the making of concrete, said apparatus comprising:

a vertical silo, through which the aggregate flows downwardly;

an air blower and heater for providing heated air for said silo;

wherein the improvement comprises a plurality of substantially horizontal, mutually crossing chute means, said chute means being mounted at successive vertical positions within said silo, each chute means forming a vaulted space thereunder, said air being delivered to said chute means and passing through said spaces, at least one of said chute means terminating in the vicinity of a crossing 3 point with another of said chute means.

2. Apparatus as described in claim 1 and further including a plurality of vertical beams within said silo, characterized in that each of said chute means is attached at one end to one of said beams and each said chute means terminates on its other end at a distance from the silo wall.

3. Apparatus according to claim 1, characterized in that both ends of the chute means are open.

4. Apparatus according to claim 1, characterized in that the vault-forming chutes rest immediately one upon the other at the crossing point.

15. Apparatus according to claim 1, wherein said silo defines a discharge opening at its lower end, and characterized in that said blower includes an intake port in relative proximity with said discharge opening of said illO in order to absorb stone dust and blow the dust back into the 5110.

t). Apparatus according to claim 5, characterized in that said blower is mounted on the bottom of the silo, to the side of the receiving funnel.

7. Apparatus according to claim 6 wherein said silo includes a receiving funnel terminating in said discharge opening, characterized in that the intake of the blower is located at the lower end of said receiving funnel of said silo, and said blower includes a blowing duct located at the upper end of said funnel.

8. Apparatus for discharging aggregate and for heating it for the making of concrete comprising:

a vertical silo having an opening at its top for receipt of aggregate components and another opening at its bottom for discharging the aggregate;

a plurality of substantially horizontal, mutually crossing vault forming members mounted at successive vertical positions within said silo, each of said members being configured as inverted chutes defining vault spaces thereunder, at least one end of each of said members terminating in the vicinity of a crossing point with another of said members; and

an air blower and heater means for blowing heated air into the vault space formed by a lowermost one of said members, heated air circulating upwardly around said members through the vault spaces. 

1. Apparatus for discharging aggregate and heating it for the making of concrete, said apparatus comprising: a vertical silo, through which the aggregate flows downwardly; an air blower and heater for providing heated air for said silo; wherein the improvement comprises a plurality of substantially horizontal, mutually crossing chute means, said chute means being mounted at successive vertical positions within said silo, each chute means forming a vaulted space thereunder, said air being delivered to said chute means and passing through said spaces, at least one of said chute means terminating in the vicinity of a crossing point with another of said chute means.
 2. Apparatus as described in claim 1 and further including a plurality of vertical beams within said silo, characterized in that each of said chute means is attached at one end to one of said beams and each said chute means terminates on its other end at a distance from the silo wall.
 3. Apparatus according to claim 1, characterized in that both ends of the chute means are open.
 4. Apparatus according to claim 1, characterized in that the vault-forming chutes rest immediately one upon the other at the crossing point.
 5. Apparatus according to claim 1, wherein said silo defines a discharge opening at its lower End, and characterized in that said blower includes an intake port in relative proximity with said discharge opening of said silo in order to absorb stone dust and blow the dust back into the silo.
 6. Apparatus according to claim 5, characterized in that said blower is mounted on the bottom of the silo, to the side of the receiving funnel.
 7. Apparatus according to claim 6 wherein said silo includes a receiving funnel terminating in said discharge opening, characterized in that the intake of the blower is located at the lower end of said receiving funnel of said silo, and said blower includes a blowing duct located at the upper end of said funnel.
 8. Apparatus for discharging aggregate and for heating it for the making of concrete comprising: a vertical silo having an opening at its top for receipt of aggregate components and another opening at its bottom for discharging the aggregate; a plurality of substantially horizontal, mutually crossing vault forming members mounted at successive vertical positions within said silo, each of said members being configured as inverted chutes defining vault spaces thereunder, at least one end of each of said members terminating in the vicinity of a crossing point with another of said members; and an air blower and heater means for blowing heated air into the vault space formed by a lowermost one of said members, heated air circulating upwardly around said members through the vault spaces. 